1. Field of the Invention
The present invention relates to a contactless communication medium.
2. Description of the Background Art
Conventionally, a technology of providing an antenna on a substrate and connecting the antenna to an IC module to form a contactless communication medium such as an IC card, an IC tag or the like which can perform data communication with an external read/write device is known (Japanese Patent Publication No. 3721520).
With the above-described conventional technology, when an inlet including an IC module mounted on an antenna sheet which has an antenna is combined with an insulating substrate or the like and the resultant assembly is used as a contactless communication medium, the substrate is made thick due to the thickness of a mold part or the like containing an IC chip sealed therein. Therefore, the inlet including the IC module mounted on the antenna sheet is combined with an inlay substrate having an opening in positional correspondence with the mold part so that the mold part is exposed from the opening.
In an IC card or the like, the outermost layer of the inlay is held between insulating resin substrates in a laminated manner; thus no serious problem occurs even with the above-described structure. However, especially, in the case where the inlay is in the outermost layer and thus the IC module part is exposed to the outermost layer, as in an electronic passport or the like, or in the case where the inlay is covered merely with a paper material or the like which is weak against electricity, the IC module is likely to be influenced by an external impact or the like. This causes malfunction or communication disorders of the contactless communication medium.